The invention relates to a system for connecting a shaft to a joint, which system comprises a shaft journal that is connected to the shaft and a sleeve that is connected to a hub of the joint. The sleeve comprises a central opening for receiving the shaft journal that is secured axially in the sleeve by a retaining ring.
Published German patent application no. DE 197 39 934 discloses a generic connection system in which a tubular shaft is connected by a shaft journal to the inner hub of a constant velocity joint so as be rotationally fixed. The shaft is secured against being pulled out of the hollow inner hub of the constant velocity joint by a retaining ring that is disposed in a peripheral groove on the shaft and that engages in a corresponding counter-groove in the inner hub. In this connection system, the shaft is secured against displacement relative to the inner hub solely by the retaining ring that supports the axial forces. In such a construction of the connection system, it is possible for an axial resistance defined by the retaining ring to be exceeded, for example, during the assembly operation in which the shaft is inserted together with the shaft journal into the hub, so that the retaining ring jumps out of the peripheral groove of the shaft, strikes the shaft through the inner hub, and penetrates the interior of the constant velocity joint. As a result, the torque-securing connection between the shaft and the inner hub can likewise be overridden.
U.S. Pat. No. 7,806,773 (=DE 10 2006 006 980) describes a hollow inner hub that is sealed on the joint side by a cover. When the shaft journal in this joint is secured only by a retaining ring, there is a risk that the shaft journal can no longer be held by the retaining ring in the case of extremely high insertion forces and the shaft journal may impact against the cover due to the high applied force and push the cover out of its mounting, thereby causing a possible leakage of lubricant and/or entry of dirt particles.
Published US patent application no. US 2007/032303 (=DE 103 42 497) describes a connection system in which a drive shaft can be inserted into a joint connection, the inner hub that serves as the joint connection comprising a central recess that is provided with a profiling for torque transmission. An appropriately corresponding profiling is provided on the shaft journal that is inserted into the central recess until a flange provided in the form of an end stop at the transition between the shaft journal and the shaft so as to extend outwardly in the radial direction abuts against the outer end face of the inner hub, as a result of which a further axial penetration of the shaft in the direction of the joint is prevented. The shaft is secured in the inner hub by a retaining ring that is disposed on the outer side of the inner hub or by a lock nut that is fitted over the flange and the thread of which engages in a thread provided on the outer side of the inner hub. As a result of the external flange extending from the shaft outwardly in the radial direction, such a solution for the connection system necessitates a large amount of space and, at the same time, increased weight and material, which conflicts with the general requirement of reducing weight, costs, fuel consumption, and CO2 emission.
Furthermore, the shaft must first be inserted into the joint connection, and then a suitable means for axially securing the shaft must be applied, as a result of which the assembly effort increases and an automatic assembly proves to be more difficult.